ultrasafe-crypto-reviewer

ultrasafe-crypto-reviewer is a skill for Claude Code from SoliEstre/EstreGenesis. It costs 186 tokens per session (7,353 once invoked), scanned A, original, Apache-2.0.

A pre-release security review that examines how an application uses cryptography, including keys, random numbers, TLS, signatures, and constant-time code. It acts as an attacker and produces advisory findings with technical references.

In plain words
What is it for?
Use it to review key handling, encryption connections, signature schemes, timing-leak risks, readiness for post-quantum cryptography, and the ability to change cryptographic methods.
Why use it?
It helps expose cryptographic mistakes before a release. The described version reports issues but does not block publishing.

Skill for Claude Code

Written for Claude Code: PreToolUse hook event. Also seen: mentions AGENTS.md.

Part of the ultrasafe plugin — 8 skills shipped together

Good fit Use it to review key handling, encryption connections, signature schemes, timing-leak risks, readiness for post-quantum cryptography, and the ability to change cryptographic methods.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/soliestre/estregenesis/ultrasafe-crypto-reviewer
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add SoliEstre/EstreGenesis --skill ultrasafe-crypto-reviewer
Clone the repo
git clone --depth 1 https://github.com/SoliEstre/EstreGenesis

Made for: Claude Code.

Or install ultrasafe, the plugin that ships this one along with the rest of its 8 skills.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for ultrasafe-crypto-reviewer

README.md
[![agentmods](https://agentmods.dev/badge/skills/soliestre/estregenesis/ultrasafe-crypto-reviewer/github.svg)](https://agentmods.dev/skills/soliestre/estregenesis/ultrasafe-crypto-reviewer)
Your own site
<a href="https://agentmods.dev/skills/soliestre/estregenesis/ultrasafe-crypto-reviewer"><img src="https://agentmods.dev/badge/skills/soliestre/estregenesis/ultrasafe-crypto-reviewer/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for ultrasafe-crypto-reviewer

Your own site · 80×15
<a href="https://agentmods.dev/skills/soliestre/estregenesis/ultrasafe-crypto-reviewer"><img src="https://agentmods.dev/badge/skills/soliestre/estregenesis/ultrasafe-crypto-reviewer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 186 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 7,353 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector warn 7 Sept 2026
SkillSpector: 1 finding, up to medium

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

  • medium Tool Misuse · line 106
    Tool defaults are unsafe or overly permissive (e.g. disabled TLS verification, no authentication, world-writable permissions). Unsafe defaults widen the attack surface.
    Fix: Override unsafe defaults with secure settings (verify=True, auth required, restrictive permissions). Review and harden all tool configurations.
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00186 $0.07353
Opus 5 $0.00093 $0.03676
Sonnet 5 $0.00037 $0.01471
Haiku 4.5 $0.00019 $0.00735

Measured 12d ago against content hash 226de7c6ef72, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

ultrasafe-crypto-reviewer scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 12d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

plugins/ultrasafe/skills/ultrasafe-crypto-reviewer/SKILL.md · 380 lines

How it starts

The opening of the file, as written. The whole thing — 380 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Crypto Reviewer — Ultrasafe Attacker Skill (v0.2.0)

Role: Agent 4 of the 8-agent Ultrasafe fan-out (Ultrasafe.md §15.4). Simulated penetration testing of the cryptographic surface, executed as an attacker — adversarial probe, not a friendly audit. Tone: crypto-formal. Findings cite RFC / NIST SP / FIPS / IETF draft anchors, not informal claims. Mode: v0.2.x advisory. Every emit carries value.advisory: true and value.permanent_manual: <bool>. No publish blocking in this cut — orchestrator surfaces findings to the live board + outbox.jsonl; release-gate verdict is informational only. Output channel: ULTRASAFE_FINDING Constellation A2A intent (commitment-tier ack, §13.13). Persistent evidence written to .ultrasafe/findings/<iter>/F-<id>.json (adopter-repo working dir — Ultrasafe.md §14.3).


§1 When to invoke

This skill is model-invoked by the Ultrasafe orchestrator role (the main agent's Workflow fan-out + the ultrasafe_run_fanout MCP tool — Ultrasafe.md §14.1 role mapping), not by direct user request. Trigger paths:

  1. Orchestrator fan-out: ultrasafe_run_fanout MCP tool (§16.1) dispatches this skill when the active axis-set includes usf-crypto. Default for all release candidates touching crypto-related files.
  2. PreToolUse hook: ultrasafe-trigger.cjs (§17.1) intercepts publish-equivalent commands (npm publish, pip upload, cargo publish, git push --tags <public-remote>, gh release create, docker push, helm push). If the staged tree touches any path in crypto_surface_globs (see §3.1), this skill is in the dispatched set.
  3. Manual iteration request: a user explicitly asks for "another crypto pass" or "re-run crypto axis" — orchestrator re-dispatches this skill with iteration: N+1.
  4. Regression probe: a prior finding's recommended_fix was applied; the orchestrator re-runs this skill to verify the patch (clean-signal check, §16.3).
  5. Inbound SECURITY_DISCLOSURE_INTAKE (§18.4) classified as cryptographic in nature — orchestrator routes the disclosure body to this skill for triage.

Read the full file on GitHub · 380 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 12d ago First seen · 380 lines · 186 tokens per session scan A 226de7c6ef72

Subscribe to this mod's changes

ultrasafe-crypto-reviewer is a skill published in the GitHub repository SoliEstre/EstreGenesis (8 stars, last pushed 6d ago), licensed Apache-2.0. It adds 186 tokens to every session and 7,353 once invoked, about $0.0009 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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